Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

What are anti-anxiety (anxiolytic) drugs?

Anxiolytics (also termed anti-anxiety or anti-panic drugs) are medications that are used to treat a health condition called anxiety. The type of anxiety that requires treatment is called generalized anxiety disorder (GAD). This disorder causes excessive worry and anxiety, significant distress, and affects the ability for a person to function. Moreover, the symptoms of anxiety occur on most days for at least six months. Generalized anxiety disorder is treated with psychotherapy and medications.

How do anti-anxiety drugs and benzodiazepines work (mechanism of action)?

Antidepressants reduce anxiety by increasing the concentration of chemicals (neurotransmitters) that the brain uses to communicate. These neurotransmitters include serotonin, norepinephrine, and dopamine.

Buspirone may reduce anxiety by stimulating serotonin and dopamine receptors on nerves, thereby altering the chemical messages that nerves receive.

Benzodiazepines reduce symptoms of anxiety by increasing the action of a brain chemical called gamma-aminobutyric acid (GABA). GABA is a chemical that nerve cells use to communicate with each other and it reduces brain activity. It is believed that excessive activity in the brain may lead to anxiety or other psychiatric disorders.

Pregabalin is an anticonvulsant. Like benzodiazepines, Pregabalin also increases the action of GABA, and this may be its main mechanism for reducing anxiety.

Some clinical studies suggest that some herbal medicines may reduce anxiety symptoms. However, many of these clinical studies are small, and there also are clinical studies that show that some herbs are not useful therapy for anxiety. Patients should consult their doctor and pharmacist before self-treating anxiety symptoms with herbal medications. Herbal medications are not a replacement for standard therapy for anxiety.

Some nutritional supplements have shown beneficial effects in small clinical studies. Examples of supplements that may be effective for reducing anxiety symptoms include:

Based on clinical studies, the effect of magnesium supplementation on anxiety symptoms may not be better than a sugar pill. Patients should consult their doctor and pharmacist before self-treating anxiety symptoms with nutritional supplements.

Researchers have looked into the effect of Yoga on improving anxiety. Some of these small clinical studies suggest that Yoga may improve anxiety symptoms by improving the levels of GABA in the brain. Since Yoga and other types of exercise are beneficial for overall health, it may be a useful addition to standard medical therapy for anxiety.

Which drugs or supplements interact with anti-anxiety drugs?

Selective serotonin reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) have many important drug interactions when they are used for the treatment of anxiety or other health conditions.

Patients should not take anxiolytic drugs with any of the monoamine oxidase inhibitor (MAOI) class of antidepressants or other drugs that inhibit MAOIs such as linezolid [Zyvox] and intravenous methylene blue. Examples of MAOIs include:

Patients that take such combinations may develop confusion, high blood pressure, tremor, hyperactivity, coma, and death. Patients may develop similar reactions if they combine SSRIs or SNRIs with other drugs that increase serotonin in the brain.

Combining SSRIs or SNRIs with warfarin, aspirin, nonsteroidal anti-inflammatory drugs (for ex-ample ibuprofen (Motrin, Advil) or other drugs that affect bleeding may increase the likelihood of patients developing upper gastrointestinal bleeding when these drugs are used for the treatment of anxiety or other health conditions.

Other drug interactions with anxiolytics

Carbamazepine (Tegretol, Tegretol XR, Equetro, Carbatrol) and rifampin reduce the blood levels of some benzodiazepines and this may reduce the effect of affected benzodiazepines when they are used for the treatment of anxiety or other health conditions.

Buspirone also interacts with MAOI class of antidepressants. Combining buspirone with warfarin (Coumadin), a blood thinner, may increase the effects of warfarin and increase the risk of bleeding in patients. Grapefruit juice increases the amount of buspirone in the blood of patients, possibly leading to side effects.

Alcohol and drugs that cause sedation may increase the sedative effects of pregabalin.

Hydroxyzine increases the drying effects of other medications that have anticholinergic effects. Combining hydroxyzine with alcohol or medications that cause drowsiness increases the chance of sedation.

Some natural herbal products and supplements like St. John's wort, ginkgo
biloba, valerian, lemon balm, and chamomile may be helpful in reducing anxiety.
Talk with your doctor about taking herbal or other supplement products.